Evaluation of various laboratory techniques to diagnose Helicobacter pylori in patients with upper gastro-intestinal tract symptoms.
Helicobacter (Campylobacter) pylori is strongly associated with type B gastritis. The detection of H. pylori, which entails histological examination and culture of gastric biopsy specimens, takes several days. There has been much interest in developing more rapid tests, including non-invasive ones. Using histology and/or culture as the 'gold standard', several methods to detect H. pylori were compared and evaluated. The organism was detected in 84 of 100 consecutive patients attending the Gastrointestinal Unit of King Edward VIII Hospital for upper gastrointestinal tract endoscopy. Histological examination was the most sensitive (98%) and specific (100%) method used in detecting H. pylori in gastric biopsy specimens. An enzyme-linked immunosorbent assay to detect specific IgG antibodies to whole H. pylori organisms is a moderately sensitive (82%), non-invasive method but it is nonspecific (38%). Although culture was specific (100%), it was less sensitive (68%) than histological examination. The 'conventional' urease assays must be performed under controlled conditions (37 degrees C) for optimal results (sensitivity, 71%).